$\dfrac{9}{100} + \dfrac{18}{10} = {?}$
Solution: The fractions must have the same denominator before you can add them. Rewrite $\dfrac{18}{10}$ as $\dfrac{180}{100}$ $\dfrac{9}{100} + \dfrac{180}{100} = {?}$ $ = \dfrac{189}{100}$